1. Field of the Invention
The present invention relates to a method of transmitting data stream including multi-angle or multi-story stream sections recorded in a recording medium to a displaying apparatus connected through a digital interface such as IEEE 1394 standard.
2. Description of the Related Art
In these days, a digital television being able to present high-quality pictures is being spread rapidly and widely.
In the meantime, a high-density DVD player (referred as xe2x80x98HDVD playerxe2x80x99) is also being developed. A HDVD player aims to reproduce data written in a high-density DVD (Digital Versatile Disk) whose recording standard is under discussion at present. For better presentation of data reproduced from a HDVD player, a HDVD player is likely to be connected to a digital television through a digital interface such as IEEE 1394 standard.
Data streams recorded in a high-density DVD may contain many multi-angle or multi-story stream sections since the storage capacity of a high-density DVD is very high. The multi-angle stream has different scenes viewed from different angles and the multi-story stream has different stories in its stream segments.
When multi-angle or multi-story stream is encountered in reproduction of a high-density DVD, a user can select desired viewing angle or story at that branching point. This operation is explained in detail with reference to the accompanying drawings. Hereinafter, the word of xe2x80x98multi-pathxe2x80x99 means multi-angle or multi-story.
FIG. 1 shows a block diagram of a HDVD player comprising an optical pickup 12 reading signals recorded in a high-density DVD 11; an analog signal processor 13 binarizing the read signals after compensating levels of the signals; a digital signal processor 14 restoring the binarized signals into digital data and separating the restored data into presentation data containing A/V data and navigation data for reproduction control; an interfacing unit 15 sending the presentation data and PCI (Presentation Control Information) data according to the navigation data to a digital television 200 connected through IEEE 1394 standard; a controller 16 controlling the above elements according to the navigation data and/or user""s commands; and a memory 17 storing data which are necessary for the control operation and are generated in data reproduction.
The interfacing unit 15 transmits the presentation data to the digital television 200 through isochronous channel of IEEE 1394, and PCI data according to the navigation data and command data generated on user""s request through asynchronous channel of IEEE 1394.
During the reproduction of the high-density DVD 11 in the HDVD player 100, as shown in FIG. 2, a multi-path stream section, for example, section B, which is composed of n section segments B-1, B-2, . . . and B-n, is encountered after an uni-path stream section A is reproduced and transmitted. When a multi-path stream section is encountered, the HDVD player 100 pauses reproduction until a path is selected by a user. If a path of multi-path stream section B, for example, the 2nd section segment B-2 is selected, the controller 16 reproduces and transmits only segment B-2 among all section segments. After transmission of the segment B-2, the controller 16 reproduces stream section C and next sections sequentially until next multi-path stream is encountered. Between a multi-path stream section and its preceding or following stream section, the digital signal processor 14 is controlled so that stream sections transmitted in succession through the isochronous channel are presented seamlessly.
The digital television 200 presents the stream sections, whose receiving sequence is . . . A, B-2, C, . . . , received through the isochronous channel into high-quality pictures on its screen.
However, to transmit stream sections including multi-path stream sections to be presented seamlessly, a high-precision control operation and a complicated algorithm are inevitable. Furthermore, in the situation that several digital televisions are connected with a single HDVD player, each viewer of each digital television can not watch program associated with his or her desired angle or story since only one stream section segment is provided among all segments recorded for a multi-path stream section.
It is an object of the present invention to provide a data stream transmitting method which copies an uni-path data stream as much as the number of multiple paths of a multi-path stream recorded in a high-density optical disk, and transmits them to an outer device through a digital interface after forming them into respective virtual channel data stream.
The data stream transmitting method according to the present invention, checks the number of maximum multiple paths of data streams recorded in a recording medium when a reproduction of the recording medium is requested, copies an uni-path stream section read from the recording medium so that the number of total same stream sections is equal to a target number larger than two which is determined based on the maximum number, assigns each stream section to a virtual channel to form multi-channel streams, and transmits the multi-channel streams to an outer device through a digital interface.